Prolactin-mediated transcriptional and post-transcriptional control of casein gene expression

Cell. 1979 Aug;17(4):1013-23. doi: 10.1016/0092-8674(79)90340-4.


The mechanism by which prolactin, a peptide hormone, regulates casein gene expression has been studied in mammary gland organ culture. After prolactin addition, a 2-4 fold increase in the rate of casein mRNA transcription was observed within 1 hr and maintained for at least 24 hr. This increased rate of transcription is not sufficient to account for the mass accumulation of casein mRNA. The half-life of casein mRNA is also increased 17-25 fold in the presence of prolactin. This change in casein mRNA half-life, coupled with a 2-4 fold increase in the rate of transcription, can account for the normal accumulation of casein mRNA observed after prolactin addition. This hormone-induced change in casein mRNA half-life appeared to be selective, since prolactin was found to exert only a slight effect (1-4 fold) on the half-life of poly(A) RNA determined under identical pulse-chase conditions. The hormonal regulation of casein gene expression thus does not app-ar to be an "all or none" process occurring only at the transcriptional or post-transcriptional levels, but rather may involve a coordinated response at several levels to permit the efficient expression of specialized differentiated functions.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Caseins / biosynthesis
  • Caseins / genetics*
  • Female
  • Genes
  • Mammary Glands, Animal / drug effects*
  • Mammary Glands, Animal / metabolism
  • Organ Culture Techniques
  • Pregnancy
  • Prolactin / pharmacology*
  • RNA, Messenger / metabolism
  • Rats
  • Time Factors
  • Transcription, Genetic / drug effects*


  • Caseins
  • RNA, Messenger
  • Prolactin